Byounghak Lee

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We describe the design and implementation of KSSOLV, a MATLAB toolbox for solving a class of nonlinear eigenvalue problems known as the <i>Kohn-Sham equations</i>. These types of problems arise in electronic structure calculations, which are nowadays essential for studying the microscopic quantum mechanical properties of molecules, solids, and other(More)
— We present a new linearly scaling three-dimensional fragment (LS3DF) method for large scale ab initio electronic structure calculations. LS3DF is based on a divide-and-conquer approach, which incorporates a novel patching scheme that effectively cancels out the artificial boundary effects due to the subdivision of the system. As a consequence, the LS3DF(More)
The Linearly Scaling three-dimensional fragment (LS3DF) method is an O(N) ab initio electronic structure method for large-scale nano material simulations. It is a divide-and-conquer approach with a novel patching scheme that effectively cancels out the artificial boundary effects, which exist in all divide-and-conquer schemes. This method has made ab initio(More)
We report experimental improvement of both RF and digital AC performance of a 28nm CMOS technology by predoping the gate poly. The results are explained in terms of the physical structure of the gate and the atomic structure of the gate TiN/Si interface in the gate stack.
Interface morphology dependent Schottky Barrier Height (SBH) and its modulation by substitutional dopants in NiSi<sub>2</sub>/Si interface have been investigated using density functional theory. An accurate band gap of Si was estimated by employing meta-GGA exchange correlation functional. We show that the SBH for electrons (in n-type semiconductor) is(More)
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